Figure 9.

Involvement of CaMK in CREB activity following Trpv1 activation in DRG neurons. Immunohistochemical analyses of CGRP and CaMKII (A–C), Trpv1 and CaMKII (D–F), CGRP and CaMKIV (G–I), and Trpv1 and CaMKIV (J–L) in DRG. DRG sections were double-stained with antibodies as indicated in the figures. Bar, 50 μm (M) DRGs isolated from rats were treated with pH 5.5 medium with or without the CaMK inhibitor KN-93, which was added 1 h before acid stimulation. The expression of CGRP mRNA was determined with real-time PCR. The data are shown as fold activation normalized to control (mean ± SD). *p < 0.05 versus pH 5.5. (N and O) Effects of KN-93 on the transcriptional activity of CREB. F11-Trpv1 cells were transfected with 3×CRE-Luc (N) or CGRP (350)-Luc, and cells were treated with pH 5.5 medium for 24 h with or without KN-93. Cells were preincubated with KN-93 for 1 h before treatment with pH 5.5 medium. The data are expressed as fold activation normalized to the untreated control (mean ± SD). *p < 0.05 versus pH 5.5.